Dyeing process for solidified drying oils



Patented Apr. 23, 1935 PATENT OFFICE DYEING rnocnss FOR soumrmn name omsVernon a. Pallas, Cortland, N.

No Drawing. Original application November 8,

1932, Serial No. 641,739. Divided and this application November 5, 1934,Serial No. 751,545

9 Claims. (Cl. 91-68) This invention relates to a novel process fordyeing and similarly treating fibriform substances such as threads,strands or braided cords, also 'textile products of silk, linen, cotton,viscose rayon or the like after they have been coated with a solidifieddrying oil, and which process is especially suited for the economicalproduction of high grade fish lines and oil coated fabrics.

The present methodis a division of my copending application, Serial No.641,739 filed November 8, 1932, as now confined to an intensive heattreating process for baking drying oils upon fibrous materials. Sincecertain aspects of the resulting product bear upon the dyeing problemherein solved, a brief definition of the aforesaid so-called dryingprocess will serve to characterize the preferred preparation to be givensuch oil coated materials for subsequent. dye treatment in an improvedmanner.

Said drying process has more specifically to do with impregnating afibrous substance with filler dope and then baking at a controlled oventemperature ranging between 100 C. and 200 C. to solidify the applieddrying oil in an oxidizing atmosphere. Several oil coatings or layercourses may be superimposed thereon to build up a pliant, homogeneousfiller body about the fibrous strand. Each of the respective coatingsmay be subjected to a separate baking period but the total time of heatapplication is preferably terminated in order to preserve the oil coatedfibrous material against inordinate deterioration in tensile strengthwhile exposed to such intensive heat treatment. The stipulatedtemperature range makes for a tough solidified oil coating that may berapidly and thoroughly oxidized without resort to chemical driers. Myfiller dope is purposely kept substantially free from pigments or otherdetrimental coloring agencies likely to addition- 40 ally weaken thetensile strength of the fibrous material by chemical reaction or tootherwise injure the quality of its solidified coating while beingsubjected to the prescribed relatively high baking temperature for aprolonged period. By virtue of a final seasoning bake applied prior tocoloring the solidified oil body, my coating is made to withstand agingwithout significant hardening or checking. Such supplemental bakingimproves the kink resisting qualities of the 50 finished product.

The object of the present invention is to devise a dyeing method thatwill allow of imparting color to a solidified, translucent drying oilparticularly when the filler is applied and baked upon a fibrous corestrand in accordance with my improved heat treating process; also toattain a uniform color distribution along such strand by dyeing inwardlyfrom its. coating exterior without allowing the core strand to becomefully saturated and thereby overcome certain intrinsic 5 coloringdifficulties heretofore encountered in the fabrication of superior fishllnes,'textlles or the like oil coated goods on a rapid productivespale.

A further objective is to provide for a durable but pliant solidifiedoil coating that shall prove suit- 10 able for fish line or fabricpurposes and by the application of the cited'seasoning bake,additionally toughen my solidified coating and render it more resistantwhen subjected to a kinkproofing test.

'It has heretofore proven difficult to dominate 15 the natural yellowcolor common to most drying oils without mixing a pigment into thefiller dope bath, but which obstacle may be surmounted by a procedurethat will hereinafter be more fully defined. As directed to thefabrication of a fish line 20 or the like product, the usual braidedline strand thereof primarily consists of silk material that may be keptwhite or undyed. Such virgin line may be impregnated with a filler dopecomposed in any constituent proportions of suitable raw or treateddrying oils, preferably without the presence of lead, manganese or thelike chemical driers, also free from pigments or the like injuriouscontamination likely to combine chemically with the fibrous strand orits coating and thereby adversely afiect the product while undergoingintensive heat treatment.

The resulting body of solidified oil remains translucent whether or notthe line strand has been initially dyed or otherwise stained. It ispreferred to introduce any other coloring matter as an ultimate step,that is to say, after all coating operations have been completed. Afiller dope of the same character is also applicable to fabrics or thelike textiles.

In conjunction with the dyeing of my oil coated product, it is preferredto include a seasoning step in my heat treatment during which the oilcoated line or fabric is exposed to a prolonged final bake of from oneto three hours at a comparatively high temperature preferably rangingfrom 140 to. 150 C. Such supplementary baking serves to more thoroughlycomplete oxidation without inordinately weakening the fibrous filament,hence fortifies my translucent fiber coating in withstanding a kinkingtest so that upon being superficially dyed, said coating will notdevelop a conspicuous localized opaqueness when subjected to suchstrain.

Exposure to high temperature generally causes the undyed oil filler ofan initially light yellow shade to become darker in color duringprotracted baking. Where a pale or other attractive light finish isdesired, I have found it expedient to first bleach or fade such productafter prolonged baking, preferably but not necessarily, by light raytreatment as distinguished from chemical bleaching. The surface of thesolidified oil coating may be exposed to strong sunlight or ultravioletrays of ample intensity until a desired lighter color shade has beenachieved. Such processing may be conducted simultaneously with one ormore of the cited baking steps. Thereupon, said bleached product may beimmersed in a suitable dye bath containing soluble, organic dyestuif orthe equivalent thereof; Glaubers salts or other aiding chemicals may beused to stimulate the dyeing process. Because of its being virtuallyimpervious to water and other dyestuff carriers, a solidified drying oilusually requires a concentrated dye solution to bring the time of colorabsorption within reasonable operative limits.

After taking on the desired color shade and the coatings have becomesuperficially impregnated with coloring matter, the removed product maybe subjected to a dye precipitating agency such as a solution of bariumchloride or the like chemical. This step fixes said dye and makes itinsoluble in water-to provide for an adequately waterproofed andnon-leaching finished product.

The aforesaid dyestuff naturally penetrates rather slowly into thesurface of an impervious oil coating of this kind, and hence thecoloring agent will be rather gradually absorbed even should theimpregnation be accelerated by means of hydrostatic pressure. Inpractice, it has proven exacting to effect an even distribution of thedye throughout the length of a fish line or the like textiles, since thethickness of the applied baked coatings are likely to vary somewhatabout the irregular surface contour afforded by the braided or twistedcore strand thereof. Furthermore, after some of the thinner coatingspots have been penetrated, the greater dye afiinity of the fibrous corematerial tends to bring about an uneven color apportionment. In order toattain a shade that shall appear substantially uniform throughout thebaked translucent drying oil, it is preferred to cease dyeing operationsprior to complete impregnation of the core material. This mode ofprocessing is likely to leave a stratum of undyed or innate yellowfiller lying immediately contiguous to depressed portions of theaforesaid irregular core surface. A silk fish line in which thesolidified filler surface rather than the braided strand has thus beenintensely stained, makes for a superior commercial product and one inwhich both the time and cost of dyeing may be materially reduced. Wherethe translucent oil coat ing of such goods has been dyed inwardly, anypronounced change in its refractive index under a sharp kinking test orthe like spotty surface imperfection may be substantially overcome by myimproved coloring process as used in combination with the prescribedseasoning heat treatment.

It may in certain instances, prove expedient to work with an initiallydyed filament which of itself would virtually impart color to thetranslucent coating baked therearound. It is generally preferredhowever, to superficially dye the innate pale color of such coating to adarker shade and thereby subdue its contrasting yellow streak so thatthe baked filler medium may be sharply kinked without vitiating thenatural transparency thereof.

The foregoing is descriptive of a method that has been foundwholly'satisfactory as applied to apparent that certain of the citedsteps may be omitted and that their described order may be rearranged.For instance, if the ultimate surface finish of such product is to bekept relatively dark in color, it may prove needless to bleach the same,particularly so if oven temperatures lower than 100 C. should beresorted to. As regards the use of the precipitating or dye fixingagency, this is primarily intended to produce a water fast article thatwill also prove reasonably color fast when exposed to sunlight. Wherewaterfastness is not a requirement, the cited dye precipitating step maybe eliminated. As a substitute for the described coloring and dyeprecipitating process, the final surface of the coated line or fabricmay likewise be stained and made waterfast in a bath of mineral oil orother dye carryi g agency that is colored with an oil soluble dyestuif.

A fish line made in accordance with my process not only handles well andremains soft and pliable, but to a marked degree solves the citedkinking problem. This end is preferably secured by working with a fillermedium which may be kept substantially pure throughout the heatprocessing steps and allowing no pigments or the like impurities to beintroduced which under intensive heat treatment, may tend to set updetrimental secondary chemical reactions. Said dyeing process also isadmirably suited to treat cloth or other woven goods of suitable texturewhich may likewise be impregnated and baked to make up table covers,window shades, raincoats, umbrella covers, and the like moderatelywaterproofed sheet materials. In such instances, the cited fillerbleaching step assumes especial importance in that it allows offinishing such goods in many handsome colors of lighter shade.

I claim as my invention:

1. The process for dyeing an oil coated fibrous filament and whichprocess comprises coating said filament with drying oil and solidifyingsaid coating in an oxidizing atmosphere, and then superficially coloringsaid coating with dyestufl and terminating the dye penetration prior toallowing the filament to become saturated.

2. The process for dyeing an oil coated fibrous filament and whichprocess comprises coating said filament with drying oil substantiallyfree from a pigment and baking in an oxidizing atmosphere at atemperature ranging between one hundred and two hundred degreescentigrade for a limited period of time that is terminated in accordancewith the actual baking temperature employed to preserve the filamentagainst inordinate deterioration while solidifying the oil coatingthereof, and then superficially applying dyestuff to said coatingwithoutallowing the dyestufi to saturate the filament.

v 3. The process for dyeing an oil coated fibrous filament and whichprocess consists in applying a series of drying oil coatings uponsaidfilament and baking the respective coatings for a length of timesufiicient to solidify the drying oil and 4. The process for dyeing afish line and which process comprises coating the line strand withdrying oil and baking in an oxidizing atmosphere at a temperatureranging between one hundred and two hundred degrees centigradefor alimited period of time that is terminated in accordance with the actualbaking temperature employed to preserve said strand against inordinatedeterioration while solidifying the oil coating thereof, thensuperficially treating the baked coating with dyestuff and thereuponfixing the penetrated dye to render the same substantially insoluble inwater.

5. The process for dyeing an oil coated fibrous filament and whichprocess consists in coating said filament with an innate pale dryingoil, baking in an oxidizing atmosphere for a prolonged period of timesufficient to solidify the coating of drying oil and darken the shadethereof and which baking is terminated in accordance with the actualbaking temperature employed to preserve the embraced filament againstinordinate deterioration while being baked, then bleaching said darkenedoil coating to a lighter shade, and thereupon dyeing the bleached oilcoating to a different color. 1

6. The process for kinkproofing a colored fish line and which processconsists in initially coloring the line strand, then coating said strandwith drying oil kept substantially free from a pigment, and lastlybaking the coated strand in an oxidizing atmosphere to dry the oil intoa solidified translucent state and which baking includes a seasoningperiod held at a temperature ranging between one hundred. and twohundred degrees centigrade without allowing the tensile strength of thestrand material to become unduly impaired during such seasoning period,said seasoning serving to convert the drying oil into a pliant body thatsubstantially maintains its translucency and correspondingly shows theoutline oi! the strand therethrough when subjected to a localizedkinking strain.

'7. The process for dyeing an oil coated fibrous filament and whichprocess consists in coating said filament with drying oil that is keptsubstantially free from impurities likely to react injuriously upon saidoil when subjected to heat treatment, then baking the coated filamentfor a limited period in an oxidizing atmosphere at a temperature rangingbetween one hundred and two hundred degrees centigrade to solidify andseason the oil coating, and thereupon superficially treating theseasoned coating with a carrying agency containing dyestufi.

8. The process for dyeing an oil coated fibrous filament and whichprocess consists in coating an initially colored filament withsemi-transparent drying oil of an innate pale color and baking thefilament in an oxidizing atmosphere to solidify the coating thereof,then superficially treating said coating with dyestufl of a shade darkerthan the aforesaid innate color to render the baked coating relativelyless transparent and thereby correspondingly mask the colored filament.

9. The process for dyeing a fish line and which process consists incoating the line strand with a translucent drying oil having an innatepale color and baking said strand in an oxidizing atmosphere for alimited period to solidify the coating thereof, and then superficiallytreating said coating with a carrying agency containing dyestufi toimpart color thereto of a shade darker than the aforesaid innate colorbut without allowing the dye to saturate the line strand.

VmNON R. PALLAS.

